properly capitalize "macOS"

Author: stephenwade

content/actions/creating-actions/about-actions.md

@@ -32,8 +32,8 @@ You can build Docker container and JavaScript actions. Actions require a metadat
 | Type | Operating system |
 | ---- | ------------------- |
 | Docker container | Linux |
-| JavaScript | Linux, MacOS, Windows |
-| Composite run steps | Linux, MacOS, Windows |
+| JavaScript | Linux, macOS, Windows |
+| Composite run steps | Linux, macOS, Windows |
 
 #### Docker container actions
 

content/actions/hosting-your-own-runners/about-self-hosted-runners.md

@@ -87,7 +87,7 @@ The following operating systems are supported for the self-hosted runner applica
 - Windows Server 2016 64-bit
 - Windows Server 2019 64-bit
 
-#### MacOS
+#### macOS
 
 - macOS 10.13 (High Sierra) or later
 

content/actions/reference/specifications-for-github-hosted-runners.md

@@ -63,8 +63,8 @@ The software tools included in {% data variables.product.prodname_dotcom %}-host
 * [Ubuntu 16.04 LTS](https://github.com/actions/virtual-environments/blob/main/images/linux/Ubuntu1604-README.md)
 * [Windows Server 2019](https://github.com/actions/virtual-environments/blob/main/images/win/Windows2019-Readme.md)
 * [Windows Server 2016](https://github.com/actions/virtual-environments/blob/main/images/win/Windows2016-Readme.md)
-* [MacOS 10.15](https://github.com/actions/virtual-environments/blob/main/images/macos/macos-10.15-Readme.md)
-* [MacOS 11.0](https://github.com/actions/virtual-environments/blob/main/images/macos/macos-11.0-Readme.md)
+* [macOS 10.15](https://github.com/actions/virtual-environments/blob/main/images/macos/macos-10.15-Readme.md)
+* [macOS 11.0](https://github.com/actions/virtual-environments/blob/main/images/macos/macos-11.0-Readme.md)
 
 {% data reusables.github-actions.ubuntu-runner-preview %}
 {% data reusables.github-actions.macos-runner-preview %}

content/github/finding-security-vulnerabilities-and-errors-in-your-code/running-codeql-code-scanning-in-a-container.md

@@ -21,7 +21,7 @@ You must run {% data variables.product.prodname_codeql %} in the same container
 You may have difficulty running {% data variables.product.prodname_code_scanning %} if the container you're using is missing certain dependencies (for example, Git must be installed and added to the PATH variable). If you encounter dependency issues, review the list of software typically included on {% data variables.product.prodname_dotcom %}'s virtual environments. For more information, see the version-specific `readme` files in these locations:
 
 * Linux: https://github.com/actions/virtual-environments/tree/main/images/linux
-* MacOS: https://github.com/actions/virtual-environments/tree/main/images/macos
+* macOS: https://github.com/actions/virtual-environments/tree/main/images/macos
 * Windows: https://github.com/actions/virtual-environments/tree/main/images/win
 
 ### Example workflow

content/github/finding-security-vulnerabilities-and-errors-in-your-code/running-codeql-code-scanning-in-your-ci-system.md

@@ -39,7 +39,7 @@ On Linux:
 chmod +x codeql-runner-linux
 ```
 
-On MacOS:
+On macOS:
 
 ```shell
 chmod +x codeql-runner-macos

data/reusables/github-actions/macos-runner-preview.md

@@ -1,5 +1,5 @@
 {% note %}
 
-**Note:** The MacOS 11.0 virtual environment is currently provided as a preview only. The `macos-latest` YAML workflow label still uses the MacOS 10.15 virtual environment.
+**Note:** The macOS 11.0 virtual environment is currently provided as a preview only. The `macos-latest` YAML workflow label still uses the macOS 10.15 virtual environment.
 
 {% endnote %}